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New camshaft bearings..but camshaft doesn't fit

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Men, need a bit of help please. I am rebuilding my 2.5L petrol engine (1988, 17H model) and just had the machine shop install new camshaft bearings. I also bought a new camshaft and when I went to install it the new camshaft doesn't fit - based on my measurements the new bearings are about .023" too small in diameter.  The old and new camshaft journals measure exactly the same. I've never heard of anyone ever having to line bore camshaft bearings before (and neither has my machinist, and he can't even do that if I wanted him to) so I'm wondering what others have done or why the camshaft doesn't fit? Any advice? Is it possible that land rover camshaft bearings come in both unfinished and finished sizes and maybe I ordered the wrong ones??

Thanks for the help.  BNA.

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I ordered the bearings from Paddocks, and had no idea there was a difference between finished and unfinished bearings.  I'm in the US and nobody anywhere near me (within a 1000 miles) has a mandrel small enough to line bore camshaft bearings. Do you know where I can buy finished bearings?  I'm not familiar with Turners...


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As we are talking about very fine tollerances here.... I would imagine that even if they were spot on size prior to fitting, they would not quite be that exact size and shape once pressed in to place inside the block.

This idea might be silly as it is straight off the top of my head, but here goes......If no one can bore the bearings once inplace for you, the only option might be to get your engineering shop to measure accurately the exact size (and shape to check for out of round) for each bearing, then grind the camshaft to size to fit each bearing.


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Bowie69 - yep not a burr, they are about .024 off in size.  Monkie - I discussed that idea with my machinist, and he agrees that should be a last resort only.

I spoke with Turners yesterday, and the engineer their said most of the time their pre-finished bearings will fit just great and that a line ream would be ideal, but if you can't do that then you should be ok with just a quick polish on the bearing inners.

Thanks for your advice everyone.

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If they are all the same amount undersize installed why not remove and bore to that much oversize , it may be good to do one in increments as it may shrink less with removal to find the optimum size . This does not replicate a proper line bore though .I would not consider grinding the cam journals down .



Steve b

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On 7/24/2017 at 0:26 PM, western said:

Turners state NOTE: after fitment it is recommended the bearings are line reamed to ensure the camshaft turns properly. Specialist equipment is required.


Yes, but almost all of the time they work without boring.  The one you get from Paddocks and the like mandate boring.

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